1. Field of the Invention
This invention relates to the elimination of odors from waste material, and more specifically to the elimination and control of ammoniacal odors from animal and human excreta. The pungent and unpleasant odor of ammonia emanating from organic waste products subject to chemical or microbial degradation is a public nuisance as well as a health hazard, particularly in situations where waste products are left to accumulate over periods of time, such as days, weeks and even months.
Ammonia is formed as the end product in the degradation of urea by the enzyme urease, and the enzyme degradation of uric acid to form urea, and then ammonia. Urea and uric acid are products of protein catabolism. In certain specific environments such as poultry houses, the concentration of ammonia in the air can become so high, that it can cause ammonia blindness in the poultry, thereby causing production losses through the reduced consumption of feed.
Ammonia fumes in pig farrowing houses can lead to respiratory illness, such as pneumonia, in piglets. The odor of ammonia is also a problem in privies, zoological gardens, and sewage treatment facilities. The keeping of domesticated pets such as cats, dogs, hamsters, guinea pigs, birds, and the like, where excreta can accumulate in cages, pens or other in-house facilities also gives rise to objectionable ammonia odors.
Many efforts have been made to ameliorate the problem of odor emanating from waste materials by the use of certain substances to cover up or "mask" the odor. However, this approach does not remove or eliminate odor, especially the ammonia odor. Other methods have dealt with controlling different odors associated with the decay of fecal and other waste materials, such as mercaptans, dialkylsulfides, hydrogen sulfide and skatole. These methods have not been successful in controlling or eliminating ammonia odors emanating from the waste materials.
2. Description of the Prior Art
A number of prior art approaches have used various chemical compositions to deal with the odor problems of various organic waste materials. U.S. Pat. No. 3,944,908 to Postrihac discloses a biological fertilizer produced from the treatment of sewage sedimentation sludge with a sulfite waste liquor at a pH of no more than 6, followed by mixing the treated sludge with pulverized vegetable matter. U.S. Pat. No. 4,108,771 to Weiss reduces odors from waste material by contacting them with an aqueous acid solution containing an oxidizing agent, for example, water soluble persulfates, nitrates, chlorates and permanganates of ammonia and alkali metals, and a precipitating agent which is a water soluble ferrous or ferric compound. Inorganic acids, such as sulfuric acid are disclosed as most efficient, although acid salts may also be employed, such as peroxydisulates (persulfates), hydrogen sulfates, ferric chloride and the like. The amount of acid material employed in the mixture is designed to provide a pH of up to about 6.5.
U.S. Pat. No. 124,041 to Dotch discloses deodorizing night soil with sulfuric and hydrochloric acid. U.S. Pat. No. 125,886 to Dotch discloses a method for deodorizing night soil and converting it into fertilizer by mixing it with sulfuric acid, hydrochloric acid, and potassium nitrate. U.S. Pat. No. 705,462 to Smith discloses a method for making fertilizer from excreta by adding it to phenol, calcium carbonate and alumina silicate.
U.S. Pat. No. 3,978,208 to Okada discloses a composition for deodorizing excrement, which contains derivatives of hydroxamic acid as the active ingredient. U.S. Pat. No. 3,989,498 to Cox discloses a deodorant composition for sewage sludge which is then spread as a slurry on land for restoring fertility. The deodorant composition contains glacial acetic acid and amyl alcohol. It can also include sulfuric acid, 2-3-butanedione, benzaldehyde, hydrochloric acid and copper sulfate. U.S. Pat. No. 4,127,383 to Johnstown et al discloses a composition consisting of a salt of lignosulfonic acid and a foaming surfactant system for use in treating nitrogenous wastes. The composition, applied to proteinaceous materials stabilizes the amines and ammonia contained therein. A foam stabilizer such as callulose gum can be an additional component.
A number of prior art approaches have also addressed themselves to the problem of deodorizing animal wastes. U.S. Pat. No. 3,983,842 to Marion et al discloses a pelleted animal litter containing as its major ingredient, ground peanut hulls with sodium bicarbonate as the odor suppressor. Other odor suppressors include calcium carbonate, trisodium phosphate and sodium carbonate. Filler materials include grass. U.S. Pat. No. 3,765,371 to Fisher prefers synthetic materials, such as high surface area foamed plastics, including polystyrene, polyurethane, phenolic resins, polyvinyl chloride, cellulose acetate, etc., rather than clays, bentonite, and alfalfa, as filler.
U.S. Pat. No. 3,735,734 to Pierce et al discloses an admixture of an absorbent such as clay or diatomaceous earth, and a deodorant, such as chlorophyl, sodium or potassium dihydrogen phosphate, or potassium acid phthalate. U.S. Pat. No. 3,675,625 to Miller et al discloses an absorbent of clay, vermiculite, or earthen material, and an odor control material such as menthol, camphor or other phenolic materials. U.S. Pat. No. 3,636,927 to Baum discloses camphane derivatives as odor inhibiting substances, along with a number of conventional solid carriers.
U.S. Pat. No. 3,352,792 to Clark et al uses a deodorant composition comprising a borate, such as borax and magnesium carbonate. U.S. Pat. No. 3,286,691 to McFadden utlilizes dehydrated grasses, preferably alfalfa and includes absorbing aids such as bentonite and trimethylquinoline. U.S. Pat. No. 3,029,783 to Sawyer et al discloses an aluminum salt and sorptive carrier.
Although several approaches have addressed themselves to the elimination and control of odors from waste materials, none of them effectively deal with ammoniacal odors. Bactericides such as 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline have also been used, but they are not effective. The state of the art approaches generally seek to deal with all odors emanating from animal and human waste materials, and, in so doing, do not successfully deal with the problem of controlling and eliminating ammonia odor.